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上周在圣地亚哥(San Diego), 业界一年一度的盛会APEX落下了帷幕。Indium公司一如既往地参加和支持APEX，并在会上发表4篇技术文章。

在展会上，我们介绍的重点仍然是Indium8.9系列的焊接产品。这些产品分有卤素和无卤素的(halogen contained or halogen free)，每种产品都有自己突出的特点，但是整个系列的产品都是针对免洗无铅(no-clean Pb-free)而设计的，可以与fine powder 兼容，能够很好的帮助客户解决枕头效应(head-in-pillow), graping 等问题。

Indium发表的技术文章可以在我们公司的网站上免费下载：http://www.indium.com/technical-documents/whitepaper/

• QFN Voding Control Via Solder Mask Patterning on Thermal Pad
• Material and Process optimization for HIP Defect Elimination
• Voiding Mechanism and Control in Mixed Solder Alloy System
• The Effects of Human-Induced Contamination on PCB Assembly Electrical Reliability

我很高兴能参加这次盛会，并见到了许多新老客户。期待明年4月份Las Vegas 的APEX.

Cheers!

PS: 隆重祝贺Indium公司的好朋友和我的好友，Intel公司的Raiyo Aspandiar 荣获Distinguished Committee Service Award (from IPC at IPC APEX EXPO in February in recognition of Raiyo’s outstanding contributions to the development of IPC-7095C, Design and Assembly Process Implementation for BGAs.) 实至名归！！…… 有的书把Steve Jobs 05年Stanford 演讲的名言”Stay hungry, stay foolish” 翻译成 “求知如渴，虚怀若谷”。 我觉得这是绝妙的翻译，也是Raiyo 的真实写照！！ 恭喜你Raiyo!!

Pic: Indium Corp

Folks,

I was at SMTAI 2011 last week and, as usual, JoAnn Stromberg and team did an amazing job.

I think SMTAI's technical program is the best around, offering scores of topics and world class speakers.  I chaired a session (MFX4) Alternate Lead-Free Alloys, with papers by Dr. Ning-Cheng Lee, Srinivas Chada, and Jasbir Bath.

I also co-authored three papers:
 
The technical sessions were extremely well attended, with 30-60 people in each.  An emerging trend is that the tech sessions are  swamped and the show floor not so much.  I think the Internet allows people to get a sense of products online, while the technical talks enable one-on-one discussions with experts in the Q&A after the papers.  It is tough to beat this interaction, even in an Internet world.

The new hot topic, to me, is the interest in "Conflict Minerals."  I participated in a panel discussion on this topic (see image).  It appears that the Dowd-Frank act will require publicly held companies to show "due diligence" in investigating their supply chain to determine if their tin, tantalum, gold, and tungsten come from "conflict" mines.  This requirement will likely ripple up and down the supply chain.  So we all need to become knowledgeable in this topic. Indium Corporation is very involved in this.

As for the venue, Forth Worth was nicer than I expected (not that a business traveler ever gets to see much). There was a nice restaurant area near the conference center. It reminded me of the Gaslamp Quarter in San Diego.  But for me, I longed for Disney World a little. Next year!

Cheers

Dr. Ron

Folks,

Some time ago, I mentioned that I was working on a consensus of the status of lead-free/RoHS compliant assembly. My hope is to find data and facts that will support the consensus. I am making progress, but at this time I would like to share the subtopics in the consensus. Look them over and see what you think:

1.       Was/Is lead-free electronics/RoHS needed to protect the environment?

2.      Is lead-free solder easier and safer to recycle than lead-containing solder?

3.      How has the increased use of tin and silver affected their supply and price?

4.      How much did it cost to implement lead-free/RoHS compliant electronics?

a.      What is the cost adder to a typical lead-free product?

5.      What are the process challenges of lead-free assembly?

a.      Are these challenges being addressed?

b.      If so, how?

6.        What is the reliability of lead-free vs leaded electronics for commercial applications?

a.      E.g. 0C to 100C thermal cycle, drop shock

7.        What is the reliability of lead-free vs leaded electronics for harsh environment/military applications?

a.      E.g. -55C to 125C thermal cycle, other Mil stress tests

8.      What is the threat of tin whiskers, tin pest and other similar lead-free related reliability phenomena?

9.      What is the status and need for halogen-free assembly?

 

Help me by suggesting topics that I have left out.     
Contact info here.
Cheers,
Dr. Ron

Many, many thanks to the hundreds of you who came by the Indium Corporation booth at Semicon West this year. Some of you came to hear about our recent global Semiconductor Assembly Materials Roadmap presentations, and all of you wanted to talk about your specific materials needs. Special thanks to those of you who shared the many successes you are having with our growing portfolio of applications-specific materials.


Based on these discussions, just a few of the topics that you will be hearing about in this blog in the coming months are:

- Lead/indium paste for multiple reflow applications onto gold pads
- Tin antimony solder paste
- Fluxes for 2.5D and 3D flip-chip applications
- Waferbumping fluxes for microbumps
- Jetting epoxy fluxes
- Tombstoning in semiconductor applications

Also: a final big THANK YOU to our friends at Nordson/Asymtek for showcasing the Indium halogen-free PoP paste Indium9.88-HF which was still dispensing after over 3 days of continuous usage at room temperature: proving its hard-earned reputation as the Energizer bunny of Pb-free (lead-free) dispense pastes. Here is a picture from the final day.

We look forward to seeing you all in 2012 (Exhibits: July 10-12th, 2012).


Cheers!  Andy

A quick trip to discuss roadmapping with one of the world’s top processor manufacturers, and a visit to discuss Pb-free power die-attach materials, left me with a few hours to spare at LAX.

This time around I was trying to work out how much package-on-package (PoP) solder paste we would expect to see for a waferlevel CSP (WL-CSP) or a BGA dipped to half height. The need for some deep thought was driven by a customer who asked at what point a PoP dipping paste needs to go from a type 4 to type 5, 6, 7 and so on (however you define them), based on the PoP/CSP pitch or ball diameter. Good question.

To start with, in order to get consistent quantities of paste on each sphere, the PoP paste metal loading needs to be well below the point at which rheopectic behavior can expect to be seen (that is, much less than 50% by volume of solder powder metal). By doing this, you pretty much guarantee a “monolayer” of solder paste powder particles (radius r) coating the CSP or BGA sphere (radius R). Figure 1 shows the kind of result that is typical for a good paste: in this instance our halogen-free PoP paste Indium 9.88-HF.



Figure 1: 0.4mm pitch CSP with PoP paste

If the metal loading is too high, even at time zero, you will start seeing large variations in the amount of PoP solder paste adhering to the surface of each sphere (bump), even on adjacent spheres: the small amount of paste that is picked up during the dipping process adheres to the main solder sphere in uneven clumps. This is why standard type 4 printing solder pastes just don’t work in PoP applications: not only is the particle size too big – the rheology is all wrong.

If R>>r, then a reasonable first order approximation is that you can treat the sphere surface as planar and so model the number of solder particles based on a series of hexagonally close-packed particles (Figure 2 gives the definitions).
 

Figure 2: Definitions for the PoP paste dipping process

Using the same model of solder powder particle size as in the discussion on waferbumping paste, you can calculate a couple of potentially useful things:

i/ The maximum number of solder powder particles on each solder sphere (bump)

ii/ The mass of solder paste adhering to each soldersphere

The first (i/) is useful for establishing the inherent variability due to the finite size of the solder powder, and I’m going to suggest another Mackie rule of thumb of a minimum 150 solder powder particles per solder bump, based on the maximum allowed particle size (diameter). The table below gives  the result of this rather simplistic analysis:



Table: Effect of Package Bump Diameter on Solder Paste Type Needed

A 400micron bump should therefore be fine even with a type 3 dipping paste, whereas a 200micron bump will need a type 5 paste.

I look forward to someone proving this wrong. The second (ii/) is helpful, because we can easily use it to test the theoretical mass of PoP dipping paste against what we actually find. Note that this is just simple geometry: it doesn't tell us how much paste is really needed to resolve issues such as the 60 - 90micron bowing we are hearing about from our customers, even with the more rigid PoP packages currently available.

Cheers!  Andy

I had a call with a few engineers today who wanted me to answer a question, “Which solder paste do I pick for my application.” Sure there were a few application-specific details that I feel were too specific to discuss with a general audience, but I think I can answer the question for any of you that are out there wondering the same question while reading this.

 

It’s an easy answer really; start with SR-8 unless:

1)     You are using laser reflow equipment.

2)     You have noticed solder spatter issues related to your design.

3)     Your company or end customers require you to use only halogen-free materials

4)     The residue must be clear and almost non-existent (ultra-low residue levels)

 

If you said “yes” to any of the above, you’ll want to try SR-7 (as long as you have nitrogen reflow capability). If you said yes to answer 3 (halogen-free) but you do not have nitrogen reflow capability, try SR-089.  

 

Jim’s note: This post was written in August 2010 – but it will be available to anyone searching for the info for quite some time. For updated information on newer solder pastes, send an email to Solar@Indium.com. Thanks! ~Jim

I mentioned in a previous a blog posting that the primary driver for halogen-free electronics is ostensibly environmental, but that the confusion about “which halogens and which molecules and what level?” has seemingly decoupled the laudable desire for an improved environment from the reality and made it more of a marketing tool. All this notwithstanding, there remain some instances where the performance of the final product itself can be directly impacted by the presence of halogens, usually as ionic halides. This is the reason why Indium Corporation recently developed what appears, at first glance, to be an odd combination: a high-Pb (high-lead) alloy halogen-free die-attach solder paste, Indium9.72-HF.

 

The halogen-related failure mode for die-attach solder pastes is the corrosion of wirebond pads on the topside of Power Semiconductor die which are soldered to the leadframe with halogen-containing solder paste. Many manufacturers producing high volumes of identical power devices may also use die-attach (sometimes called “soft solder die attach”, SSDA) wire to attach the die to the leadframes in a fluxless process, but many manufacturers prefer the inherent flexibility of a solder paste-based process for medium mix / medium volume applications.

 

Long term blog readers will recall that I did a posting on solderspatter (a.k.a. soldersplatter or soldersplash), and that it can be caused by bubbles of solvent vapor or moisture outgassing from solder paste deposits during reflow. In bursting, the tiny flux droplets or solder particles from the surface of the bubble can be propelled quite a distance (several feet). While solder on wirebond pads is clearly a failure from a reliability viewpoint, certain wirebond pad metallizations may also be subject to corrosion from flux. A poorly maintained reflow oven may also drip flux condensate (usually in the exit – cooling – zone), and this too can be a cause of organic materials on wirebond pads.

 

As long as the bondwire is gold, and wirebond pads are covered in a uniform layer of gold, there is no problem (as long as the flux residue is washed off) since gold is unreactive, even in corrosive environments. Aluminum (Al) or aluminum/silicon (Al/Si) bondpads, however, are potentially reactive. Halogenated materials, such as fluxes and overmolding compounds may react with them to either reduce the wirebond pull strength and/or increase the wirebond junction resistance, leading to localized heating and subsequent thermal-related joint failure. Even covalently-bonded (C-X, where X is a halogen) materials may dissociate at high temperatures: which is how the banned brominated flame retardants work, of course.

 

The biggest danger of halogenated flux corroding wirebond pads is when:

 

1/ Completed assemblies (between the reflow process and the cleaning process) are left for a long time before cleaning; particularly if they are exposed to high humidity (high %RH) before cleaning.

 

2/ The cleaning process is inadequate: either due to poor selection of the cleaning solution, or poor bath maintenance, or inadequate “scrubbing” energy being imparted to the surface to be cleaned, or simply if inadequate time is allowed for cleaning.

 

Note that even optimizing 1/ and 2/ may still lead to bondpad corrosion.

 

The Indium9.72-HF paste is available in both type 3 and 4 powder, in the standard high-Pb alloys, Indalloy 151 (92.5Pb/5Sn/2.5Ag) and Indalloy 163 (95.5/2Sn/2.5Ag), and for larger die that need a higher reliability joint, we also offer the Indalloy 164 (92.5Pb/5In/2.5Ag). A Product Datasheet is available for download, of course.

Cheers! Andy

上週在美國的拉斯韋加斯(Las Vegas), IPC舉辦了美國地區行業的盛會APEX.   Indium公司一如既往的在展會中心安排展位，和業界各位舊友新友交流，與大家分享最新的產品和技術，傾聽大家的反饋和聲音。

 

除此，在人山人海的技術會議交流中心(paper presentation, educational workshop)，Indium公司的五位大將還為大家做了精彩的演講：

• Ning-Cheng Lee, Ph.D, Vice President of Technology 李寧成博士：

²       Lead-Free Flux Technology and Influence on Cleaning.

²       Selection of Dip Transfer Fluxes and Solder Pastes for PoP Assembly.

²       Achieving High Reliability Low-Cost Lead-Free SAC Solder Joints Via Mn or Ce Doping.
 

• Ronald C. Lasky, Ph.D. PE, Senior Technologist

²       Achieving High Reliability for Lead-Free Solder Joints – Materials Consideration

• Mario Scalzo, Senior Technical Support Engineer

²       Addressing the Challenge of Head-in-Pillow Defects in Electronics Assembly.

²       Challenges for Implementing a Halogen-Free Process

• Eric Bastow, Senior Technical Support Engineer

²       Understanding SIR

• Chris Anglin, Applications Development Engineer

²       Stencil Printing Transfer Efficiency of Circular vs. Square Apertures with the Same Solder Paste

 這些文章在Indium的技術網站上面，都可以免費下載。

 

Cheers!

 

I love watching a good basketball game, and one of my favorite local teams is the Syracuse Orangemen. If you go to a Syracuse home game, notice the shot clock – it was made with Indium Corporation solder. There are a lot of places you can see our products in your everyday life. That smart phone in your pocket, the electrical components in your car, the thermal interface in the computer in front of you. That’s one of the things that makes this job rewarding, being part of so many various applications.

 

In addition to learning about these different applications, we also get a good reference for what assembly trends are developing, and which material technologies are becoming more popular. 

 

I’ve watched the halogen-free trend explode and fade, as it was adopted by some large OEMs and their contract manufacturers, but has not spread to most other companies. Another trend that is fading away from the spotlight is Pb-free die-attach solder, since the EU has not found a suitable replacement and has pushed back the exemption deadline. 

 

A long-existing topic that has had recent mention is solder jetting. The trend towards soldering smaller components is not new or surprising, but for smaller components (01005s and 0201s) we have seen a trend towards dispensing instead of jetting – which seems to suit those applications.

 

For small component printing, transfer efficiency is critical. Outside of solder paste optimization, “nano-stencil” technology is an upcoming technology that may take-off and improve paste release characteristics. Solder paste is being used in some other creative ways too, like low temperature alloy dipping paste for rework operations. Manycompanies are now using or evaluating specialized solder applications to replace components without fully reflowing the rest of the components on the board.

 

Integrated preforms are finding their way into more and more applications recently as well. These connected preforms are being used to reduce the need for component pallets and selective soldering operations.

All these applications are great ways that our customers are taking soldering technology to the next level, using materials and assembly methods that were not common before. I look forward to learning how you’d like to use solder in your application!

 

After a quick survey of a few of the technical service personnel in the office today, I put together a little snapshot of what is happening right now:

 

Amanda Hartnett and Ed Briggs are conferencing with an engineer that Amanda met at a local SMTA meeting.  This potential customer asked for product recommendations to improve their assembly process after they heard about Indium 8.9HF (a halogen free solder paste).

 


Brandon Judd is working on reducing voiding via profile modification with our flux coated preforms.

 

Mario Scalzo is tracking and organizing our technical team’s submissions to the Silver Quill program, where authors at Indium Corporation are recognized for technical papers and presentations.

 

Eric Bastow is helping a customer determine the best soldering materials for a medical application which involves soldering nitinol to nitinol. Common choices are using flux #2 or flux #3 with Indalloy 121 or Indalloy 182 – depending on the application.

 

And you’re reading what I’m doing right now. One interesting thing that I realized today is how we are working on very different things at the same time, both reactively and proactively. While some of us are fixing customer issues, others are helping to plan future processes to eliminate the need for a fix. 

 

Something that may not be apparent from this daily description is how this technical team works together. One of the nice things about being in the same office is that we can share ideas and learn from the experiences of our peers.  Even an office mate's tech call or brainstorm session can be a learning exercise. Working together gets us ready for your next call, so we can have the answer for you before it is even asked.

All the best
~Jim H

 Register at GlobalSpec to see Andy Mackie, Jim Hisert and me discuss various aspects of Green Electronics Manufacturing.  This live event will occur tomorrow (December 9, 2009) at 2 PM EST.

Andy will be discussing halogen-free and what it really means to semiconductor packaging and PCB Assemblers.

Jim will discuss solar photovoltaic cells and how material selection impacts their performance.

I will be discussing Pb-Free and some of the emerging legislation and manufacturing challenges.

Following the discussion, there will be an opportunity for attendees to submit additional questions on any of the topics.  The discussion will be full of technical information on all of the topics and, best of all, it is FREE!

As a supplier of electronics materials, Indium Corporation is constantly faced with customer requests for “halogen-free” (HF) soldering fluxes and associated materials. This is an interesting trend, but we face several challenges here:

1/ What is “halogen-free”? We have not seen any consistent message from our customers on what they mean by a halogen-free flux. As a materials-supplier this is an absolute show-stopper.

 

Based on several conversations with interested parties, my understanding of the IPC status is as follows, and apologies for any misunderstandings to Tim Jensen (Indium Corp.) and Tom Newton (IPC). The IPC’s 4-33a Task Group, which was looking at a universal halogen-free material standard (J-STD-709), saw a failure of a second ballot on the standard, even when it got downgraded to a guideline. The 4-33a group faced numerous differences of opinion: on what materials should be included; what halogen levels are allowable; or even whether a single component could be considered a "homogeneous material” to be ground up and analyzed for halogens and so on. The task of defining HF will now reportedly be taken up by two separate groups from IPC and JEDEC.

 

Meanwhile, in March of this year, the Japanese organization JEITA quietly released their understanding (ET-7304) of what is meant by HF fluxes and solder pastes, using a 1000ppm halogen limit. This definition is clearly at odds with the IEC's definition of HF. That is, 900ppm by weight maximum of chlorine or bromine atoms, or a maximum of 1500ppm of both: the so-called “9-9-15” limit. .

 

2/ Which halogens? The strict definition of a Group VII element (halogen) is one of Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I) and radioactive Astatine (At). From environmental reasons, chlorine and bromine in halogenated fire-retardant (HFR) materials that emit dioxins and similar compounds when heated should be eliminated. However, some customers are also throwing fluorine and iodine into this definition, too. This may be based on fears of electrical reliability, but from my perspective the customer is becoming defocused from the necessity of meeting environmental concerns.

 

3/ Does halogen = halogenated fire retardant? Not every halogen found in an electronic material is an indicator of a halogen-containing fire retardant!

 

Greenpeace is the main driver behind this, and I have, to date, been unable to get a response from them on how they will detect halogens on circuit boards. The fear from our customers, and our customers’ customers, is that an electronic device (iPhone / flat-screen TV or other) will be obtained by an environmental group; pulled apart; and X-ray fluorescence (XRF) used to detect halogens. The minimum sample size that can give a quantifiable result for halogen-free is reportedly 2grams: contrast this with the milligrams of material (residue) present from a no-clean flux in a cellphone, and you can see the issues in quantifying halogen levels based on flux residues. We can’t do it reliably.

 

4/ How can we confirm “zero” halogens? Contrast the JEITA standard with the requests from many customers for zero halogens / “no intentionally added” halogens / “elemental halogen-free” fluxes or some such. However, since many customers insist on third-party data-reporting, we are reliant on these analytical labs to reliably give us data. One of the challenges we face is when, for example, a lab reports “63ppm of chlorine”, based on a reported limit of detection (LOD) of 50ppm. Our customer is outraged: “You said it was halogen-free!”

 

Those of you familiar with the statistics of analytical chemistry will immediately see the two fallacies here: the first is that they have reported not the method detection limit (MDL), but the much-lower LOD. The MDL is a function of analytical equipment PLUS the errors in sample preparation and handling. The second fallacy is that you can not report 63ppm as a reliable, reproducible number, since the limit of quantitation (LOQ) – the limit at which you can actually give a figure for the concentration – is more than 3 x the MDL. The limit of analytical capability to reliably quantify the amount of halogen present is therefore around 150ppm or greater.

 

Instead of reporting “63ppm halogen”, a more accurate statement is: “In our single test, we found a small peak in our spectrum at the same elution time as a halide-ion. It may be a halogen, or it could be one of the millions of anionic organic species that elute at the same retention time. The quantity found is well below the method detection limit, so we have no way of knowing if it is from contamination during the sample preparation, and we certainly can not tell how much is present.”

 

5/ What is a ‘homogeneous material”? Some customer standards require the level of halogen in a homogeneous material to be reported. We can probably safely say that a flux is a “homogeneous material”, but is a solder paste truly homogeneous? Both JEITA and Indium Corporation can agree that the flux-content needs to be the focus of the analysis, but a solder paste supplier may, for example, take the analysis of a 90%w/w metal solder paste, and report the results as “890ppm chlorine”, knowing that the level in the (10%) flux is 8,900ppm chlorine, essentially diluted by the 90% metal content.

 

Conclusion:

 

As a global electronics materials supplier, we at Indium Corporation can see three possible solutions to all these dilemmas:

 

a/ Adopt the JEITA specification – even though it goes against the 9-9-15 EIC recommendation. This allows us to be on a level footing with our Japanese competitors, but appears to put us at odds with the needs of some of the semiconductor assembly and electronics assembly industries.

 

b/ Adopt a three-tier specification based on the IPC/IEC recommendation – the Indium Corporation approach is given here (below).



Why three levels? Because our more discriminating customers are telling us that truly halogen-free fluxes are simply not as effective as those that contain small amounts of halogen. For those who are concerned about end product reliability, a “halogen-compliant” tier allows the best of both worlds.

 

c/ Report the atomic chlorine and bromine levels present in the flux component, and allow the customer to choose what they want, based on this.

 

If you are a user of Indium Corporation materials, or even a competitor of ours - what makes most sense here? Or is there a fourth or fifth way?

Cheers! Andy

在Indium公司的主页www.indium.com , 有一个技术文章模块“New Technical Papers”。 如果你点击进入，就可以免费下载Indium公司的各种技术文章。

在这一周美国的SMTAI 2009展会上，Indium 公司一共主持6场技术文章演讲/研讨会， 还有Dr. Ron Lasky在开幕式上主讲对未来25年SMT行业的远景展望。 所以这些文章/演讲，都是围绕目前SMT行业中的三个热点/挑战：

•      微型化    Miniaturization 
•      无铅        Lead Free
•     无卤素    Halogen Free

Indium公司的技术文章以及和研讨会上的演讲，都将会和大家分享我们的研发/技术成果，以及我们是怎么样来迎接这些挑战的。

Enjoy & Cheers!  

Pic: Indium Corporation

Solder Basics...  If I needed to pick my favorite flux for hand soldering, it would easily be PoP Flux 030B.  I know it’s probably never going to find itself in household soldering toolkits, it’s a semiconductor packaging material – most people never need that good of a flux around the house, but I said it was my favorite, not the most practical. 

 

This is why PoP Flux 030B is the best choice around the house:

 

1) It has proven it’s solderability to ENIG, silver, oxidized copper, OSP, and nickel with Pb free and Sn/Pb alloys (which I’d choose any day for my personal soldering applications).

2) It is a halogen free, no-clean flux, so you can just leave it on the pipes, connectors, or stereo wires you’re connecting.

3) It is safe to use even if it isn’t completely heated and cured – this is rare for a no-clean flux.

4) The airless packaging process gives it a unique tack/viscosity ratio and a smooth texture that you just don’t get with cheapo off-the-store-shelf fluxes.

5) It activates at a relatively low temperature but can endure ~300degC reflow.  Hand soldering is not accurate, so I like the widened process window.

6) I think it’s pretty cool to use such an advanced flux for low-tech soldering, it’s overkill at its finest.

 This is a rare photo taken in the underground Structural Solder Joint Test Facility (SSJTF) nearly 5 miles below a small farming town in Central NY.  The light that you see is not really just a cellar window…

Got contacted last week by Tony Hilvers of the IPC (Association Connecting Electronics Industries). Tony tells me that the Canadian Government is considering banning some rosin and resin-based chemicals that may be of interest to flux formulators for both no-clean; solvent-clean; and even water-wash solder pastes and fluxes. The Canadians are at an early, investigative, stage here: allowing the various interested parties six months to respond.

My initial, knee-jerk reaction is as follows:

1/ While Tony and the IPC's rapid response is commendable, note that we in the electronics industry are not alone. Even a cursory Google search shows that the vast majority of these types of material are used in the following, multi-billion dollar, industries:

- Paper manufacturing

- Cosmetics

- Adhesives and glues

- Synthetic rubbers

- Coatings

- Printing inks and toners

We in the electronics industry are relatively small fry: combining our voice with that from these other industries, may give the Canadians pause for thought.

2/ If you're wondering why I'm so interested in this, it's simply because after the Pb-free switch in most of the Electronics Assembly industry, I am now seeing the Electronics Assembly and Outsourced Assembly and Test industries still in turmoil over the exact meaning of "halogen-free" solder fluxes. Industry sources are telling me that there is a strong movement to pull back from  the absolutist "zero tolerance for halogens of any kind" to a more rational call for a certain limit to them, based around the standard "9-9-15" halogen classification. The hard truth is that truly "no-intentionally-added" (NIA: that is, TOTALLY halogen-free) solder fluxes may, in some instances, simply not be as effective as those containing moderate amounts of halogens.. More on "halogen-free" in a couple of weeks.

3/ Eliminating rosins and rosin-derivatives, including materials that may be present in naturally-occurring rosin products, may not only have the beleagured Canadian timber industry up in arms, but will probably result in another protracted round of setting of allowable limits for "proscribed substances" some of which.... umm.... occur naturally.

All comments, corrections and clarifications gratefully received.

Cheers!  Andy

In many halogen-free discussions, the primary emphasis is on Bromine (Br) and Chlorine(Cl).  However, the halogens also include Fluorine(F), Iodine(I), and Astatine(At).  Most of us know several uses of F and I, but what is this element At?  

As it turns out, Astatine is is the rarest of all naturally occurring element.  According to Wikipedia, there is less than an ounce in the entire Earth's crust.  I think that means it is safe to assume we don't have to worry about it showing up in printed circuit boards!

Since At is extremely radioactive, I highly recommend avoiding it if you see some on the sidewalk but don't worry too much about it in your halogen-free testing.

最近小忙，只能凑凑杂文，不好意思。

1． 先请教大家一个问题，在太阳能光伏薄膜技术(PV Thin Film Technology)中, 哪种技术在中国领先？爲什麽呢？ 太阳能光伏薄膜技术，主要有这几种：

• Amorphous Silicon (a-Si): 非晶硅
• CIGS: 铜铟镓硒(Copper Indium Gallium Selenium)
• CdTe: 碲化镉   

2. 关于公司裏的开会。 前天中午看牙医，他又准备给我嘴巴里面打麻醉针了。"怎么这次又打？我还以为这次的小治疗不需要了。怎么每次下午我要开会发言，都会遇上你的麻醉针？叫我等会怎么说话呀？"牙医问"会议很重要吗？"我郑重其事的回答"当然！无论和谁开会，每一个会议都是重要的。因为除了自己能给会议带来value之外，也是展现自己的机会，别人也会在心中评价你的…"牙医笑道"Such a corporate girl! Please be quiet for now."然后他毫不手軟一针下来，我这个talking-box (话匣子)也慢慢地少话了…Anyway, 在公司里面，对于每一个会议都认真对待，做好准备，應該沒錯的。下次我看牙医前要问清楚是否要打麻醉针了，不然很有可能会一边说话一边不自觉地流口水的。

3.  无卤化 (Halogen-Free): 明天开始会去美国西部休假10天。我知道自己会被那里的更纯净的自然景色给shock的，也更加会想起祖国（或是第三世界国家）在电子垃圾废墟中的人们(e-waste)…还是老话，今天，你无卤化了吗？   

Greenpeace continues to take unusual steps to push electronics companies to produce halogen-free products.  On Tuesday July 28th, Greenpeace activists climbed onto the roof of one of the HP buildings in Palo Alto to protest that HP is not moving fast enough to remove BFR's and PVC from their products.

It seems to me that HP is taking their time to figure out whether or not the alternatives are both safe, reliable, and cost effective.  It would make no sense to eliminate a hazardous material and replace it with something more hazardous.  The main reason for Greenpeace's protest is that Apple has already successfully eliminated virtually all of their use of BFR's and PVC.  However, the business model of HP and Apple are much different.  HP has to be very cost consious and has a much broader product range than Apple.  HP must be very careful in selecting alternatives that will work in all their products AND allow them to be competitive in the ultra-competitive computer market. 

 The humerous Dilbert cartoon reiterates an important fact about companies "going green."  While there are probably individual employees at the company who are passionate about helping the environment, the sole purpose of the company is to make money.  Companies use terms like "environmentally friendly," "reduced carbon footprint," and "green" to create a positive impression the the consumer which is designed to lead to more sales.

In many of the IPC Halogen-Free meetings, people would ask why go through such an undertaking.  Other people have asked  to wait for scientific methodologies for determining which halogens are actually bad.  Those questions ultimately don't matter.  The process is about developing a system that companies can refer to in order to make their claims of being better for the environment (and ultimately make more money).

Eliminating halogens may actually be better for the environment, but it is still too soon to tell.  We have no idea how good/bad the alternatives are.  Unfortunately, if switching to an unknown material allows the company to put a green sticker on it, then they don't have the incentive to carry out further testing on those alternatives.

In a follow-up to my previous posting, Greenpeace's rationale for giving Apple marginal rankings on BFR and PVC elimination seem to be somewhat misguided.  In the "Guide to Greener Electronics," they applaud Apple for making the move to almost completely eliminate BFR and PVC from their products.  However, Greenpeace added: "But Apple fails to score top marks in this criterion because it uses unreasonably high threshold limits for BFRs and PVC in products that are allegedly PVC-/BFR-free." 

If you go to the Apple and the Environment website, you can see that they are not only eliminating BFR's and PVC.  Apple is the only company that I am aware of that is specifically focusing on the complete elimination of Br and Cl.  This is much more stringent than the path of other electronics companies.  Apple is a part of the IPC committees in which halogen thresholds are determined.  They are following the same thresholds as everyone else: <900 ppm Cl, <900 ppm Br, and <1500 ppm Br+Cl.  Therefore, Apple uses the same thresholds as everyone else, but includes all forms of Br and Cl (not just BFR and PVC). 

Cl and Br show up as "contamination" in many chemicals, so guaranteeing that there is ZERO Br or Cl is impossible from a practical and cost perspective.  In addition, there is significant variability in the testing procedure.  Because of that, it is possible to test something with 100-200 ppm of Br and not actually detect it.   I wonder what threshold Greenpeace would find acceptable???  The acceptable level should be determined by hazard/risk assessments, availability of materials, and capability/repeatability of a test method for that material.  Based on my knowledge of soldering and flux chemistries, I don't think the 900, 900, 1500 limit is "unreasonably high."